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In this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, are presented.

An analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections is presented. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors.

In this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, is presented. The required yield and plastic moments in this model are provided as an extension to Roark's relationships. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors. A reasonable agreement has been found between the analytical model results and the experimental/numerical modeling results.

This article is extracted from the author’s doctoral thesis, and all its achievements belong to the authors of the article.

This paper aims to investigate analytical electromagnetic fields and thrust ripples representation of linear flux-switching motors with simple modulated secondary referred as segmented secondary linear flux-switching motor (SSLFSM).

SSLFSMs are applicable to transportation systems like Maglev due to their simple and consequently low-cost secondary structures and high force density. However, they have high thrust ripples that deteriorate a smooth motion in rail transportation systems. Therefore, derivation of accurate analytical models for thrust ripples minimization of the motor is essential, which is absent in the literature. In this paper, a two-dimensional analytical model is developed for this motor. The model is based on transfer relations and Fourier theory used for solving a two-dimensional boundary value problem. Certain model regions are determined by considering actual machine structure and observing specific rules. Analytical solution of Maxwell and Poison equations are then obtained in the regions.

Using the presented modeling method, the airgap electromagnetic field distribution and developed thrust of the motor are calculated for different positions of the motor as well as its thrust ripples. They are verified by the results obtained from finite element method. Also, the analytical results are compared with the presented experimental results.

This paper has analytically presented the airgap electromagnetic field distribution, thrust and thrust ripples of the SSLFSMs. This modeling is essential in thrust ripples minimization of the motor.

The business benefits envisaged for BIM represent the main criteria for decision-making about BIM implementation – or shy away from BIM. Despite the significance, traditional evaluation techniques have difficulty to capture “the true value” of BIM from multiple levels and dimensions – as an effective evaluation method is supposed to. This study aims to identify the significant factors that affect BIM return on investment (ROI), develop an integrated model for companies and examine the influence of intangible returning factors of BIM on the rate of BIM implementation.

A cluster sampling technique was used; 92 questionnaires completed by Australian architecture, engineering and construction small- and medium-sized enterprises (SMEs) provided the basis to identify and analyse the key measurable returning factors, value drivers and strategic benefits associated with BIM ROI.

Applying the PLS-SEM technique, findings reveal that a lack of reliable quantification methods for the ROI factors associated with BIM significantly affects the organisation's commitments to implement BIM. In essence, the failure to adequately identify and assess these benefits could result in the system not being appropriately implemented and supported by executive sponsors, who give priority to hard and tangible ROI measurements.

The outcome of this study would be of direct appeal to policymakers, industry professionals and the academic community alike, in providing data-informed insight into the intersection between the implementation of BIM and the concept of ROI. Findings would provide a springboard for further research into using ROI factors to increase BIM implementation. Though the findings are directly applicable and contextualised for Australia, they provide lessons and offer a blueprint for similar studies in other countries and settings. That is, regardless of the context, findings raise awareness and provide a point of reference for the quantification of intangible returning factors rather than the tangible returning factors, as one of the first studies in its kind.

The study provides original insight in drawing attention to an untapped area for research in BIM implementation, namely BIM ROI. Apart from raising awareness around BIM ROI, the study is novel in providing a quantified model that establishes the links and level of impacts of various factors associated with BIM ROI. Findings of this study, particularly add value to the body of knowledge related to the business implications associated with BIM implementation in the context of Australian SMEs, while providing lessons for other countries and settings.

Technological entrepreneurship has been a very significant topic in recent decades. It has a crucial role in economic modernization and growth. The need for technological entrepreneurship is because technology-based industries are expanding rapidly and are replacing traditional industries. Therefore, this study aimed at identifying the factors affecting the success of technological entrepreneurship in Iranian nanotechnology businesses.

The research was conducted through mixed method. The participants in the qualitative section included 17 university experts and executive managers in the field of nanotechnology in Iran, and 75 nanotechnology business managers participated in the quantitative section. The interview and questionnaire were used to collect information. In order to measure and fit the models, the confirmatory factor analysis method and PLS3 software were used.

The results indicated that the key factors affecting the success of the technological entrepreneurship process in nanotechnology were classified into five general categories: organizational, environmental, institutional, individual and technology factors. Moreover, it was shown that all these dimensions had a positive and significant effect on technological entrepreneurship. In addition, the organizational dimension has an essential role.

Companies' ability to engage technological entrepreneurship is a vital factor in human resource management and strategic management. However, technological entrepreneurship in Iranian nanotechnology businesses has not been involved integrally in the context of companies.

Project portfolio management (PPM) is a commonly used technique to align projects with strategy and to ensure adequate resourcing for projects. In this paper, to gain a better understanding of PPM dynamics, a system dynamics (SD) model was developed. To do so, an Iranian independent power producer was used as a case study in the energy sector; moreover, policy options were derived and generalized for such a developer company.

To cope with the complexity of business processes in a power producer company and to formulate an optimum policy, causal relations and loops were derived first and then state-flow diagrams were designed to simulate the problem in the system, as it is usual in the SD methodology.

The proposed model was applied to a real-world case study to rectify managers’ viewpoint about their business dynamics and to formulate new project portfolio strategies to improve the viability of the company. The model proved how a static portfolio analysis can misguide managers in planning their project portfolio strategies, and how effective feedback can improve PPM in developing companies in the energy sector.

Systems approach, especially SD methodology, has been rarely used to analyze PPM problems in the energy sector. This study highlights the implications of feedback and dynamics in PPM and tries to derive optimal value of portfolios.

The purpose of this study is to systematically review the existing literature on the blood supply chain (BSC) from a network design perspective and highlight the research gaps in this area. Moreover, it also aims to pinpoint new research opportunities based on the recent innovative technologies for the BSC network design.

The study gives a comprehensive systematic review of the BSC network design studies until October 2021. This review was carried out in accordance with preferred reporting items for systematic reviews and meta-analyses (PRISMA). In the literature review, a total of 87 studies were analyzed under six main categories as model structure, application model, solution approach, problem type, the parties of the supply chain and innovative technologies.

The results of the study present the researchers’ tendencies and preferences when designing their BSC network models.

The study presents a guide for researchers and practitioners on BSC from the point of view of network design and encourages adopting innovative technologies in their BSC network designs.

The study provides a comprehensive systematic review of related studies from the BSC network design perspective and explores research gaps in the collection and distribution processes. Furthermore, it addresses innovative research opportunities by using innovative technologies in the area of BSC network design.

The barriers to integrating sustainable practices into construction project management require extensive resource allocations to resolve. Within developing countries such as Iran (where resources are scarce), remedial strategies adopted must prioritise tackling those barriers that can be expected to yield maximum return on investment. The candidate barriers are many, and this paper aims to identify a hierarchy of barriers, providing a priority list of remedial targets.

A mixed philosophical stance of interpretivism and post-positivism is adopted within a deductive approach and survey strategy. A list of 30 known barriers are identified from extant literature and used to formulate a questionnaire data collection instrument administered within the Iranian construction industry. Data collected from 176 practitioners are analysed using the relative importance index and Mann–Whitney U test to compare groups based on the participants' demographic variables.

The findings challenge the common assumption that items related to market and workforce experience are major inhibitors of change. That is, economics and regulatory dependent barriers have a higher impact on the failure of a shift to sustainable practices in Iran. The most influential barriers to incorporating sustainability in construction projects are: (1) lack of understanding of the potential benefits; (2) insufficient cooperation among practitioners, research institutions and environmental organisations; and (3) a lack of a systematic approach to pursuing sustainability goals. No significant associations are detected between the affiliation of the respondents and their attitude towards the issue. Thus, a generalised approach can be applied to a broader range of organisations and construction projects in Iran.

While studies on sustainability impediments at the firm or project level are ubiquitous within literature, this research identifies that the most significant barriers to sustainable project management in Iran, as an underexplored context, are those experienced at the economic and institutional level. Moreover, this novel research presents important insights into the potential effects of participants' demographic profiles on their view of the importance of identified barriers.

The amalgamation of integrated project delivery (IPD) and building information modelling (BIM) is highly recommended for successful project delivery. However, IPD lacks an accurate cost estimation methodology at the “front-end” of projects, when little project information is available. This study aims to tackle this issue, through presenting analytical aspects, theoretical grounds and practical steps/procedures for integrating target value design (TVD), activity-based costing (ABC) and Monte Carlo simulation into the IPD cost structure, within a BIM-enabled platform.

A critical review was conducted to study the status of cost estimation within IPD, as well as exploring methods and tools that can enhance the cost estimation process for IPD. Thereafter, a framework is developed to present the proposed methodology of cost estimation for IPD throughout its entire stages. A case project is used to validate the practicality of the developed solution through comparing the profit-at-risk percentage for each party, using both traditional cost estimation and the proposed solution.

After applying the proposed IPD's cost estimation framework, on a real-life case project, the findings demonstrated significant deviations in the profit-at-risk value for various work packages of the project (approximately 100% of the finishing package and 22% of openings package). By providing a precise allocation of overhead costs, the solution can be used in real-life projects to change the entire IPD cost structure and ensure a fair sharing of risk–rewards among the involved parties in IPD projects.

Using the proposed methodology of cost estimation for IPD can enhance the relationship among IPD's core team members; all revealed financial deficiencies will be considered (i.e. compensation structure, profit pooling), hence enhancing the IPD performance.

This paper presents a comprehensive solution for integrating BIM and IPD in terms of cost estimation, offering three main contributions: (1) an innovate approach to utilise five-dimensional (5D) BIM capabilities with Monte Carlo simulation, hence providing reliable cost estimating during the conceptual TVD stage; (2) mathematical models that are developed through integrating ABC into the detailed 5D BIM to determine the three IPD's cost structure limbs; and (3) a novel mechanism of managing cost saving (rewards) through distinguishing between saved resources from organisation level, to daily task level, to increase trust among parties.

This paper aims to address a distributed assembly permutation flow-shop scheduling problem (DAPFSP) considering budget constraints and factory eligibility. The first stage of the considered production system is composed of several non-identical factories with different technology levels and so the factories' performance is different in terms of processing time and cost. The second stage is an assembly stage wherein there are some parallel work stations to assemble the ready parts into the products. The objective function is to minimize the maximum completion time of products (makespan).

First, the problem is formulated as mixed-integer linear programing (MIP) model. In view of the nondeterministic polynomial (NP)-hard nature, three approximate algorithms are adopted based on variable neighborhood search (VNS) and the Johnsons' rule to solve the problem on the practical scales. The proposed algorithms are applied to solve some test instances in different sizes.

Comparison result to mathematical model validates the performance accuracy and efficiency of three proposed methods. In addition, the result demonstrated that the proposed two-level self-adaptive variable neighborhood search (TLSAVNS) algorithm outperforms the other two proposed methods. Moreover, the proposed model highlighted the effects of budget constraints and factory eligibility on the makespan. Supplementary analysis was presented by adjusting different amounts of the budget for controlling the makespan and total expected costs. The proposed solution approach can provide proper alternatives for managers to make a trade-off in different various situations.

The problem of distributed assembly permutation flow-shop scheduling is traditionally studied considering identical factories. However, processing factories as an important element in the supply chain use different technology levels in the real world. The current paper is the first study that investigates that problem under non-identical factories condition. In addition, the impact of different technology levels is investigated in terms of operational costs, quality levels and processing times.